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        <h2>
          <span class="refentrytitle">taninv2</span>
        </h2>
        <p>taninv2 — 
      Returns an arctangent.
          </p>
      </div>
      <div class="refsect1">
        <a id="idp157840080"></a>
        <h2>Description</h2>
        <p>
      Returns the arctangent of <span class="emphasis"><em>iy/ix</em></span>, <span class="emphasis"><em>ky/kx</em></span>, or <span class="emphasis"><em>ay/ax</em></span>.
    </p>
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      <div class="refsect1">
        <a id="idp157842576"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>taninv2</strong></span> ay, ax</pre>
        <pre class="synopsis">ires <span class="command"><strong>taninv2</strong></span> iy, ix</pre>
        <pre class="synopsis">kres <span class="command"><strong>taninv2</strong></span> ky, kx</pre>
        <pre class="synopsis">...<span class="command"><strong>taninv2</strong></span>(ky, kx)... (no rate restriction)</pre>
        <p>
      Returns the arctangent of <span class="emphasis"><em>iy/ix</em></span>, <span class="emphasis"><em>ky/kx</em></span>, or <span class="emphasis"><em>ay/ax</em></span>. If <span class="emphasis"><em>y</em></span> is zero, <span class="emphasis"><em>taninv2</em></span> returns zero regardless of the value of <span class="emphasis"><em>x</em></span>. If <span class="emphasis"><em>x</em></span> is zero, the return value is:
      </p>
        <div class="itemizedlist">
          <ul class="itemizedlist" style="list-style-type: disc; ">
            <li class="listitem">
              <p><span class="emphasis"><em>π/2</em></span>, if <span class="emphasis"><em>y</em></span> is positive.</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>-π/2</em></span>, if <span class="emphasis"><em>y</em></span> is negative.</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>0</em></span>, if <span class="emphasis"><em>y</em></span> is 0.</p>
            </li>
          </ul>
        </div>
        <p>
    </p>
      </div>
      <div class="refsect1">
        <a id="idp157856752"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>iy, ix</em></span> -- values to be converted
    </p>
      </div>
      <div class="refsect1">
        <a id="idp157858464"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>ky, kx</em></span> -- control rate signals to be converted
    </p>
        <p>
      <span class="emphasis"><em>ay, ax</em></span> -- audio rate signals to be converted
    </p>
      </div>
      <div class="refsect1">
        <a id="idp157861136"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the taninv2 opcode. It uses the file <a class="ulink" href="examples/taninv2.csd" target="_top"><em class="citetitle">taninv2.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp157862912"></a>
          <p class="title">
            <strong>Example 919. Example of the taninv2 opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
<span class="comment">; Audio out   Audio in</span>
-odac           -iadc    <span class="comment">;;;RT audio I/O</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o taninv2.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="comment">; Initialize the global variables.</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 4410
<span class="ohdr">ksmps</span> <span class="op">=</span> 10
<span class="ohdr">nchnls</span> <span class="op">=</span> 1

<span class="comment">; Instrument #1.</span>
<span class="oblock">instr</span> 1
  <span class="comment">; Returns the arctangent for 1/2.</span>
  i1 <span class="opc">taninv2</span> 1, 2

  <span class="opc">print</span> i1
<span class="oblock">endin</span>


<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="comment">; Play Instrument #1 for one second.</span>
<span class="stamnt">i</span> 1 0 1
<span class="stamnt">e</span>


<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />

      Its output should include a line like this:
      </p>
        <pre class="screen">instr 1:  i1 = 0.464</pre>
        <p>
    </p>
      </div>
      <div class="refsect1">
        <a id="idp157867968"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="taninv.html" title="taninv"><em class="citetitle">taninv</em></a>
    </p>
      </div>
      <div class="refsect1">
        <a id="idp157870112"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: John ffitch</td>
          </tr>
          <tr>
            <td>University of Bath/Codemist Ltd.</td>
          </tr>
          <tr>
            <td>Bath, UK</td>
          </tr>
          <tr>
            <td>April 1998</td>
          </tr>
        </table>
        <p>
    </p>
        <p>Example written by Kevin Conder.</p>
        <p>New in Csound version 3.48</p>
        <p>Corrected on May 2002, thanks to Istvan Varga.</p>
        <p>Available as a function in version 6.00</p>
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